Patent GB-981776-A (GB)
Title: Improvements in or relating to punching machines
IPC: B21D28/04
Filed: 1961-04-07
Abstract: 981,776. Punching. HOUDAILLE INDUSTRIES Inc. April 7, 1961 [Nov. 1, 1960], No. 40289/64. Divided out of 981,775. Heading B3W. A punching machine comprises a single pair of relatively reciprocable tools, each being non-circular in cross-section, and supports for each tool which are angularly adjustable about a common axis through the tools and can be locked in any selected rotational position about said axis, in all of which positions the single pair of tools can be operated. A punching machine including the tool supports comprises a C- shaped frame 31 having upper and lower arms 31a and 31b respectively. The lower arm 31b supports a sub-table 50, on which is mounted a work supporting table 33, and also supports a bed 38 on which the lower tool is mounted. A punch and stripper assembly 40 is supported by an upper tool support 41 which is held to the upper arm by clamps 42 and 43. The support 41 comprises arms 41a and 41b and between them is a reciprocating shaft 47 continuously driven by an eccentric 46 and selectively coupled to a ram 44 by an electrically operated clutch of the type described in Specification 890,250. The work supporting table is carried by a sub-table 50 so that it can be moved independently of the die bed 38. Lower tool mounting, Fig. 4.-The support for the die 39 is secured to the lower arm 31b and includes a pad 69 to which is screwed a bolster 70 having a recess 72 which receives a cylindrical member 73, also held by screws and locked against rotation by a key 87. An element 75 is a sliding fit in the member 73 and of such a length as to define a recess to receive the die 39. Removal of the die is facilitated by a pin 76 which is moved axially by an eccentric 82 formed on a shaft 77 which has a handle 78. To fix the angular position of the die a key 91 is accommodated in a radial keyway 89 formed in the member 73 and a corresponding keyway 92 in the die. A further keyway may be formed in the die, spaced 90 degrees from the first. Infinitely variable angular positioning of the die is achieved by the provision of a ring 94 which seats in a recess 93 in the member 73, and which is secured to one side of the key 91. When the ring is inverted from the position shown in Fig. 4 the key 91 is still engaged with the keyway 92 but is free of the keyway 89, so that the die and ring are free to rotate to any position, the ring subsequently being locked by a plurality of screws 95. Upper tool mounting, Fig. 5.-The upper tool support 41 is recessed to receive a flanged member 97 which can be locked in any position by screws 98, and which has a keyway 111 which receives one end of a key 113. A punch and stripper assembly 99 is slidable in the annular member and comprises a sleeve 100 within which is a punch driver 101. A punch 109 is retained in the punch driver by a screw 110 and locked against rotation by a key 116. The punch driver has a keyway 112 which receives the other end of the key 113 which passes through and is secured in, the sleeve 100. A stripper 118 is attached to the sleeve 100 by a spring clip 119, and a series of stripper springs 105 act between the upper end of the sleeve 100 and a ring 106 which engages, with the punch driver 101, the underside of a driver head 107. A set of lifting springs 117 acts between the flanged member 97 and the assembly 99 to bias the assembly away from the die. Aligment of punch and die, Fig. 6.-When the punch and die are of non-circular cross-section, angular alignment is achieved by removing the die 39 and the assembly 99 and fitting a lower aligning tool 120 and an upper aligning tool 121 which have keyways corresponding to those on the die and the punch assembly, the lower tool having alignment pins 122 which enter recesses 123 in the upper tool 121. The angular position of the punch and die relative to the work table is indicated by indices on the member 97 and corresponding graduations on the support 41 which form a vernier scale. Adapters for small-sized tools, Fig. 8.-Small sized punches are held in the machine by an alternative upper tool support 132 having a bight portion 132c which receives a punch and stripper assembly 133. A rotatable sleeve 135 which can be locked by radially positioned screws and which has a keyway 136, slidably receives a sleeve 139 which in turn receives a punch 138. Secured in the punch is a key 137 which engages the keyway 136, and screwed to the stem 239 is a punch head 140. Stripping springs 143 and 144 act between the punch head and the sleeve 139. A lifting plate 145 engages the underside of a flange on the sleeve 139 and is acted on by springs 146 which bear on the sleeve 135. Small sized dies are fitted to the die support by an adapter ring 149 which corresponds externally to the die 39 and which has a die seat 149a in which a die 150 is received. The adapter 149 has two keyways 152, 153 and the die 150 has a key 151. A filler plate 154 rests on the adapter 149 to close the gap between the die 150 and the relatively large aperture in the table 33.